The global crisis has hit Asia hard,and it may take some time before the region’s economies recover,the International Monetary Fund(IMF) commented in its latest report on Asia and the Pacific.
The long-path differential optical absorption spectroscopy （LP-DOAS） technique was developed to mea- sure nighttime atmospheric nitrate radical （NO3） concentrations. An optimized retrieval method, resulting in a s...The long-path differential optical absorption spectroscopy （LP-DOAS） technique was developed to mea- sure nighttime atmospheric nitrate radical （NO3） concentrations. An optimized retrieval method, resulting in a small residual structure and low detection limits, was developed to retrieve NO3. The time series of the NO3 concentration were collected from 17 to 24 March, 2006, where a nighttime average value of 15.8 ppt was observed. The interfering factors and errors are also discussed. These results indicate that the DOAS technique provides an essential tool for the quantification of NO3 concentration and in the study of its effects upon nighttime chemistry.展开更多
为解决复杂动态环境下全自主移动机器人路径规划存在的效率低、适应性差及多目标权衡难题,提出全自主移动机器人全局最优路径智能规划方法。利用图注意力网络与空间重构单元提取环境的全局最优路径特征,采用改进基于密度的带噪声应用空...为解决复杂动态环境下全自主移动机器人路径规划存在的效率低、适应性差及多目标权衡难题,提出全自主移动机器人全局最优路径智能规划方法。利用图注意力网络与空间重构单元提取环境的全局最优路径特征,采用改进基于密度的带噪声应用空间聚类(Density-Based Spatial Clustering of Applications with Noise,DBSCAN)算法实现静态/动态障碍物与通行区的精准划分,构建长短期记忆(Long Short-Term Memory,LSTM)运动预测模型与多传感器融合的障碍物轨迹预测模型。在改进蚁群算法框架下进行全局路径搜索,引入路径长度、时间、安全及能耗的复合权重。采用3次B样条曲线平滑优化路径,引入曲率约束以抑制龙格现象。实验显示,该方法在低负载时段平均路径偏差降低约33%,重规划次数减少约66%,动态避障成功率提高至98%;高负载时段平均路径偏差降低40%,重规划次数减少约52%,成功率达95%。展开更多
文摘The global crisis has hit Asia hard,and it may take some time before the region’s economies recover,the International Monetary Fund(IMF) commented in its latest report on Asia and the Pacific.
文摘The long-path differential optical absorption spectroscopy （LP-DOAS） technique was developed to mea- sure nighttime atmospheric nitrate radical （NO3） concentrations. An optimized retrieval method, resulting in a small residual structure and low detection limits, was developed to retrieve NO3. The time series of the NO3 concentration were collected from 17 to 24 March, 2006, where a nighttime average value of 15.8 ppt was observed. The interfering factors and errors are also discussed. These results indicate that the DOAS technique provides an essential tool for the quantification of NO3 concentration and in the study of its effects upon nighttime chemistry.
文摘为解决复杂动态环境下全自主移动机器人路径规划存在的效率低、适应性差及多目标权衡难题,提出全自主移动机器人全局最优路径智能规划方法。利用图注意力网络与空间重构单元提取环境的全局最优路径特征,采用改进基于密度的带噪声应用空间聚类(Density-Based Spatial Clustering of Applications with Noise,DBSCAN)算法实现静态/动态障碍物与通行区的精准划分,构建长短期记忆(Long Short-Term Memory,LSTM)运动预测模型与多传感器融合的障碍物轨迹预测模型。在改进蚁群算法框架下进行全局路径搜索,引入路径长度、时间、安全及能耗的复合权重。采用3次B样条曲线平滑优化路径,引入曲率约束以抑制龙格现象。实验显示,该方法在低负载时段平均路径偏差降低约33%,重规划次数减少约66%,动态避障成功率提高至98%;高负载时段平均路径偏差降低40%,重规划次数减少约52%,成功率达95%。
